Hybrid Schooling May Be the Most Dangerous Option of All

It's supposed to be the perfect compromise between in-person and online education. It could end up as a public health nightmare.
Photo-Illustration: Sam Whitney; Getty Images 

As we head toward the start of the academic year, schools around the country are grappling with how to educate their students while keeping everybody safe. Some districts will have kids back in class full-time, while others will only teach them via a screen. But an estimated 20 to 30 percent of the nation’s school districts—including New York City, which alone serves more than 1 million students—are planning to implement a hybrid model, where groups of kids attend in person on alternating, part-time schedules. US governors, school chancellors, and state epidemiologists have touted this approach as the Goldilocks solution: The number of children in classrooms is kept low enough for proper social distancing, while students still receive some amount of essential in-person learning. It appears to be the perfect compromise.

But this widely held assumption may be grossly incorrect.

“The hybrid model is probably among the worst that we could be putting forward if our goal is to stop the virus getting into schools,” says William Hanage, an epidemiologist at Harvard’s T.H. Chan School of Public Health. “I don’t see how, in the end, this helps teachers,” says Jennifer Nuzzo, an epidemiologist at Johns Hopkins Bloomberg School of Public Health. “I don’t fully get the hybrid model.”

Their argument is simple: If you want to limit children and teachers’ exposure to infection, it’s better to have students spend their time within a consistent group of peers.

In a hybrid model, when students are kept out of school for multiple days each week, or every other week, a sizable percentage of them are likely to intermingle with other children and adults. This is especially so for younger kids with working parents, as the kids may need to be in day care, exposing them to another set of social contacts and all of their possible infections. Meanwhile, older kids and adolescents will be inclined to hang out with their peers on their copious "off" days. (In many districts, remote learning plans include just a short amount of livestreamed teaching every day, leaving many hours to fill in other ways.) The hybrid model, Nuzzo says, “only works if students stay home, alone, during all of that time they are out of school.” This is a strangely unrealistic assumption by policymakers.

All those extra interactions are more likely to increase transmission risk than to reduce it, according to Dimitri Christakis, a pediatrician and epidemiologist at the University of Washington School of Medicine and the editor in chief of JAMA Pediatrics. “There’s a real chance a hybrid model could advance the spread of the virus.” In his view, it would be preferable to have 30 kids in a classroom, even if there weren’t sufficient space for 6-foot social distancing, than to switch off groups of half that size. In the latter scenario, each of those students would likely be exposed to more people overall. Their teachers, too, would be at higher risk—since instead of teaching one cohort every day, they’d be in charge of two.

Martin Kulldorff, a biostatistician at Harvard Medical School, frames it as a simple matter of arithmetic: “With full-time schooling, children primarily are in just two places and with two groups of people, at school and at home. With a hybrid model, many young children must also be in a third place with additional people, such as a grandparent, uncle, neighbor, nanny, or day-care provider.” By increasing everyone’s exposure from two places or groups to three, he says, the hybrid model is “the worst of both worlds.” He suggests a “hybrid-teacher” model, instead: The children stay in school full-time, while the most vulnerable teachers work permanently off-site, helping their colleagues to grade exams, prepare course material, or provide online tutoring for children who must be at home themselves.

While a number of countries in Europe implemented a hybrid strategy this past spring, none of the experts interviewed for this article were aware of any studies on its effects on viral transmission. Beyond the potential for greater spread of infection, the educational benefits of the hybrid model may be somewhat marginal. Meira Levinson, an educational expert and ethicist, told me that some students might find real value in even intermittent opportunities to learn in person—from dissecting frogs, for example, or the occasional team-building exercise. But some will find the inconsistency hard to handle. She also pointed out that hybrid models do little to ameliorate the child-care crisis that results from having children on remote-learning schedules.

How did we arrive at a situation where schools in at least 30 states may thrust students into a scheduling model that may actually increase the risk of viral spread to themselves and their teachers?

The hybrid schedule exists solely as a kludge and back-formation from the standard 6-foot guideline for social distancing. School reopening instructions from the US Centers for Disease Control and Prevention recommend that “students remain at least 6 feet apart.” Many states have adopted this requirement. But to comply, lots of schools will have to reduce their total populations; some by as much as two-thirds. News photos of administrators stretching tape measures between desks have become commonplace. Six feet is the cornerstone, and all the plans for hybrid schooling build from this constraint.

As many experts have pointed out, 6 is not a magic number for disease prevention. The rule of thumb originated with CDC guidance from many years ago to help prevent transmission of respiratory diseases between clinicians and patients in a health care setting. It was not based on studies of the school environment; nor specifically for young children, who may be less likely than adults to become infected with Covid-19 or to transmit the virus. The World Health Organization and the American Academy of Pediatrics each cite 3 feet as a sufficient distance to achieve benefits.

In May, Denmark reduced its social-distancing recommendations from 2 meters (6.6 feet) to 1 meter (3.3 feet) and there were no outbreaks emanating from schools. In Sweden, lower schools remained open for the entire academic year without specifying a minimum distance between students, and government reports concluded schools were not drivers of transmission and that teachers were at no greater risk than other professionals.

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Some state guidelines, such as those from Massachusetts and Colorado, acknowledge the competing public-health advice. They encourage districts to aim for 6 feet of distancing but say that 3 feet also would provide “substantial benefits” when combined with other safety measures. Nevertheless, in much of the country policymakers and school districts have seized on this single metric of 6 feet as if it were handed to Moses on a stone tablet.

My own district, in New York state, has proposed a hybrid schedule where students, including my children, aged 9 and 11, will attend class only two days per week. In fact, like a zealot overinterpreting scripture, the district plans to implement a distancing protocol based on 44 square feet per student, which it claims to have derived, somehow, from the 6-foot distancing guidelines. (That’s about 60 percent more space than should be necessary, based on simple math.) Our district’s classrooms are not overcrowded. Yet, as it stands, students will be out of school for more than half of each week, potentially increasing the risk both to themselves and their teachers, even as they incur the harms of remote learning.

When I reached out to the New York State Department of Health for clarification on whether it was advisable for schools to exceed the distancing guidelines, even if that meant the difference between students being able to attend school full-time or not, I was told that “school districts can always do more.”

The question is: more of what?

Updated, 8/7/2020, 5:30pm EST: This story has been updated to clarify that Meira Levinson argues that some kids—as opposed to many kids, as previously stated—will have trouble with the inconsistent schedule of hybrid schooling.


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